package com.greet.aspect;

import com.greet.annotation.AutoFill;
import com.greet.constant.AutoFillConstant;
import com.greet.context.BaseContext;
import com.greet.enumeration.OperationType;
import lombok.extern.slf4j.Slf4j;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.Pointcut;
import org.aspectj.lang.reflect.MethodSignature;
import org.springframework.stereotype.Component;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.time.LocalDateTime;

/*
* 自定义切面，实现公共字段的自动填充处理逻辑
* */
@Aspect
@Component
@Slf4j
public class AutoFillAspect {
    /**
     * 切入点
     */
    @Pointcut("execution(* com.greet.mapper.*.*(..)) && @annotation(com.greet.annotation.AutoFill)")
    public void autoFillPointCut(){}

    /*前置通知
    * 进行公共字段赋值
    * */
    @Before("autoFillPointCut()")
    public void autoFill(JoinPoint joinPoint) throws NoSuchMethodException, InvocationTargetException, IllegalAccessException {
        log.info("开始进行公共字段填充");
        //获取拦截到的方法的操作类型 INSERT UPDATE
        MethodSignature signature = (MethodSignature)joinPoint.getSignature();
        AutoFill autoFill = signature.getMethod().getAnnotation(AutoFill.class); //获得方法上的注解对象
        OperationType operationType = autoFill.value(); //注解对应的参数
        //获取被拦截方法的参数--实体对象
        Object[] args = joinPoint.getArgs();
        if (args == null || args.length == 0){
            return;
        }

        Object entity = args[0];

        //准备赋值的数据
        LocalDateTime now = LocalDateTime.now();
        Long currentUserId = BaseContext.getCurrentId();

        //根据当前不同的操作类型为对应的属性赋值
        Method setUpdateTime = entity.getClass()
                .getDeclaredMethod(AutoFillConstant.SET_UPDATE_TIME, LocalDateTime.class);
        Method setUpdateUser = entity.getClass()
                .getDeclaredMethod(AutoFillConstant.SET_UPDATE_USER, Long.class);
        if (operationType == OperationType.INSERT){
            Method setCreateTime = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_TIME, LocalDateTime.class);
            Method setCreateUser = entity.getClass().getDeclaredMethod(AutoFillConstant.SET_CREATE_USER, Long.class);
            //通过反射为对象赋值
            setCreateTime.invoke(entity, now);
            setCreateUser.invoke(entity, currentUserId);
        }
        setUpdateTime.invoke(entity, now);
        setUpdateUser.invoke(entity, currentUserId);
    }

}
